Figure 2.

Inhibition of mitochondrial metabolism changes both intracellular and extracellular metabolites in human RPE cells. (A) Experimental design for quantifying intracellular and extracellular metabolites caused by mitochondrial dysfunction. Mitochondrial electron transport chain shuttles electrons from NADH and FADH to O₂ to produce ATP. We inhibited complexes I, III, or V with their specific inhibitors, piericidin, antimycin, or oligomycin, respectively, in primary cultured RPE cells to investigate the impact of mitochondrial dysfunction on intracellular metabolites. Media and cells were collected at different time points as indicated and quantified by targeted metabolomics. (B–E) Scores plots of metabolites in cells and media at 1, 6, and 24 h by PLS-DA. (F) The number of changed metabolites in the medium at 1, 6, and 24 h, and in RPE cells. (G) The number of changed metabolites in different pathways in the medium at 1, 6, and 24 h. (H) Mitochondrial inhibitors decreased the levels of high-energy metabolites in cells. N = 3. *P < 0.05, **P < 0.01, *P < 0.001 vs the cells treated with DMSO. PCr, phosphocreatine.